Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New study shows Antarctic ice shelf is thinning from above and below

13.05.2015

A decade-long scientific debate about what’s causing the thinning of one of Antarctica’s largest ice shelves has now been settled. The Larsen C Ice Shelf – whose neighbours Larsen A and B collapsed in 1995 and 2002 – is thinning from both its surface and beneath. The research, by scientists from the UK and the US, is published today (Wednesday 13 May) in The Cryosphere, an open access journal of the European Geosciences Union (EGU).

For years scientists were unable to determine whether it is warming air temperatures or warmer ocean currents that is causing the Antarctic Peninsula’s floating ice shelves to lose volume and become more vulnerable to collapse. This new study takes an important step forward in assessing Antarctica’s likely contribution to future sea-level rise.


BAS radar sledge on the Larsen Ice Shelf

The research team combined satellite data and eight radar surveys captured during a 15-year period from 1998–2012. They found that Larsen C Ice Shelf, which is some 50,000 km2 in area or about half the size of Iceland, lost an average of four metres of ice, and had lowered by an average of one metre at the surface.

Lead author Paul Holland, a climate scientist at the British Antarctic Survey, says: “What’s exciting about this study is we now know that two different processes are causing Larsen C to thin and become less stable. Air is being lost from the top layer of snow (called the firn), which is becoming more compacted – probably because of increased melting by a warmer atmosphere. We know also that Larsen C is losing ice, probably from warmer ocean currents or changing ice flow.

“If this vast ice shelf – which is over two and a half times the size of Wales and 10 times bigger than Larsen B – was to collapse, it would allow the tributary glaciers behind it to flow faster into the sea. This would then contribute to sea-level rise.”

The Antarctic Peninsula is one of the fastest warming regions on Earth, with a temperature rise of 2.5°C over the last 50 years.

The team, who continue to monitor the ice shelf closely, predict that a collapse could occur within a century, although maybe sooner and with little warning. A crack is forming in the ice which could cause it to retreat back further than previously observed. The ice shelf appears also to be detaching from a small island called Bawden Ice Rise at its northern edge.

Glaciologist David Vaughan, Director of Science at British Antarctic Survey, says: “When Larsen A and B were lost, the glaciers behind them accelerated and they are now contributing a significant fraction of the sea-level rise from the whole of Antarctica. Larsen C is bigger and if it were to be lost in the next few decades then it would actually add to the projections of sea-level rise by 2100.

“We expect that sea-level rise around the world will be something in excess of 50 cm higher by 2100 than it is at present and that will cause problems for coastal and low-lying cities. Understanding and counting up these small contributions from Larsen C and all the glaciers around the world is very important if we are to project, with confidence, the rate of sea-level rise into the future.”

The study published today in The Cryosphere was carried out by scientists from the British Antarctic Survey, the United States Geological Survey, University of Colorado, University of Kansas and Scripps Institution of Oceanography.

###

Please mention the name of the publication (The Cryosphere) if reporting on this story and, if reporting online, include a link to the paper (http://www.the-cryosphere.net/9/1005/2015/tc-9-1005-2015.html) or to the journal website (http://www.the-cryosphere.net).

Photos of the Larsen C ice shelf, as well as interviews with Paul Holland and David Vaughan, are available from the British Antarctic Survey ftp site .

Notes

The Antarctic Peninsula is an area of rapid climate change and has shown one of the biggest increases in temperatures (primarily in winter) observed anywhere on Earth over the past half-century. Climate records from the west coast of the Antarctic Peninsula show that mean annual temperatures in this region have risen by 2.5°C during the last 50 years – several times the global average and only matched in Alaska.

An ice shelf is the floating extension of the grounded ice sheet. It is composed of freshwater ice that originally fell as snow, either in situ or inland and brought to the ice shelf by glaciers. As they are already floating, any disintegration of ice shelves will have no impact on sea level. Sea level will rise only if the ice held back by the ice shelf flows more quickly into the sea.

More information

This is an edited version of a release provided by the British Antarctic Survey Press Office.

The research is presented in the paper ‘Oceanic and atmospheric forcing of Larsen C ice-shelf thinning’ published in the EGU open access journal The Cryosphere on 13 May 2015.

Citation: Holland, P. R., Brisbourne, A., Corr, H. F. J., McGrath, D., Purdon, K., Paden, J., Fricker, H. A., Paolo, F. S., and Fleming, A. H.: Oceanic and atmospheric forcing of Larsen C Ice-Shelf thinning, The Cryosphere, 9, 1005–1024, doi:10.5194/tc-9-1005-2015, 2015.

The team is composed of P.R. Holland, A. Brisbourne, H. F. J. Corr (British Antarctic Survey [BAS], Cambridge, UK); D. McGrath (US Geological Survey Alaska Science Center and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, US); K. Purdon, J. Paden (Center for Remote Sensing of Ice Sheets, University of Kansas, Lawrence, US); H. A. Fricker, F. S. Paolo (Scripps Institution of Oceanography, University of California, San Diego, US); and A. Fleming (BAS).

The work is funded by the Natural Environment Research Council in the UK, National Science Foundation in the US and a range of international funding bodies around the world.

The European Geosciences Union (EGU) is Europe’s premier geosciences union, dedicated to the pursuit of excellence in the Earth, planetary, and space sciences for the benefit of humanity, worldwide. It is a non-profit interdisciplinary learned association of scientists founded in 2002. The EGU has a current portfolio of 17 diverse scientific journals, which use an innovative open access format, and organises a number of topical meetings, and education and outreach activities. Its annual General Assembly is the largest and most prominent European geosciences event, attracting over 11,000 scientists from all over the world. The meeting’s sessions cover a wide range of topics, including volcanology, planetary exploration, the Earth’s internal structure and atmosphere, climate, energy, and resources. The EGU 2016 General Assembly is taking place in Vienna, Austria, from 17 to 22 April 2016. For information about meeting and press registration, please check http://media.egu.eu closer to the time of the conference, or follow the EGU on Twitter and Facebook.

If you wish to receive our press releases via email, please use the Press Release Subscription Form at http://www.egu.eu/news/subscribe/. Subscribed journalists and other members of the media receive EGU press releases under embargo (if applicable) 24 hours in advance of public dissemination.

British Antarctic Survey (BAS), a component of the UK’s Natural Environment Research Council (NERC), delivers and enables world-leading interdisciplinary research in the Polar Regions. Its skilled science and support staff based in Cambridge, Antarctica and the Arctic, work together to deliver research that uses the Polar Regions to advance our understanding of Earth as a sustainable planet. Through its extensive logistic capability and know-how BAS facilitates access for the British and international science community to the UK polar research operation. Numerous national and international collaborations, combined with an excellent infrastructure help sustain a world leading position for the UK in Antarctic affairs. For more information visit: www.antarctica.ac.uk.

Links
Scientific paper: http://www.the-cryosphere.net/9/1005/2015/tc-9-1005-2015.html
Journal – The Cryosphere: http://www.the-cryosphere.net
British Antarctic Survey (BAS): http://www.antarctica.ac.uk
This release, including additional images and video, on the BAS website: http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=2989

Contact

Paul Holland
Climate Scientist, British Antarctic Survey
Cambridge, UK
Tel: +44 (0)1223 221444
Email: pahol@bas.ac.uk

David Vaughan
Director of Science
British Antarctic Survey
Email: dgv@bas.ac.uk

Athena Dinar
Press and Information Officer, British Antarctic Survey
Cambridge, UK
Tel: +44 (0)1223 221441, +44 (0)7909 008516
Email amdi@bas.ac.uk
BAS on Twitter: @BAS_News

Bárbara Ferreira
EGU Media and Communications Manager
Munich, Germany
Tel: +49-89-2180-6703
Email: media@egu.eu
EGU on Twitter: @EuroGeosciences

Bárbara Ferreira | European Geosciences Union

More articles from Earth Sciences:

nachricht In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>